Brecker Lothar, Schwarz Alexandra, Goedl Christiane, Kratzer Regina, Tyl Catrin E, Nidetzky Bernd
University of Vienna, Institute of Organic Chemistry, Währinger Strasse 38, A-1090 Wien, Austria.
Carbohydr Res. 2008 Aug 11;343(12):2153-61. doi: 10.1016/j.carres.2007.12.023. Epub 2008 Jan 11.
Saturation transfer difference NMR spectroscopy is used to study non-covalent interactions between four different glycostructure transforming enzymes and selected substrates and products. Resulting binding patterns represent a molecular basis of specific binding between ligands and biocatalysts. Substrate and product binding to Aspergillus fumigatus glycosidase and to Candida tenuis xylose reductase are determined under binding-only conditions. Measurement of STD effects in substrates and products over the course of enzymatic conversion provides additional information about ligand binding during reaction. Influences of co-substrates and co-enzymes in substrate binding are determined for Schizophyllum commune trehalose phosphorylase and C. tenuis xylose reductase, respectively. Differences between ligand binding to wild type enzyme and a corresponding mutant enzyme are shown for Corynebacterium callunae starch phosphorylase and its His-334-->Gly mutant. The resulting binding patterns are discussed with respect to the possibility that ligands do not only bind in the productive mode.
饱和转移差异核磁共振波谱法用于研究四种不同糖结构转化酶与选定底物和产物之间的非共价相互作用。所得的结合模式代表了配体与生物催化剂之间特异性结合的分子基础。在仅结合条件下测定底物和产物与烟曲霉糖苷酶以及纤细假丝酵母木糖还原酶的结合情况。在酶促转化过程中测量底物和产物中的STD效应可提供有关反应过程中配体结合的额外信息。分别针对裂褶菌海藻糖磷酸化酶和纤细假丝酵母木糖还原酶，确定了共底物和辅酶对底物结合的影响。展示了棒状嗜盐碱杆菌淀粉磷酸化酶及其His-334→Gly突变体中配体与野生型酶和相应突变酶结合的差异。针对配体不仅以生产性模式结合的可能性，对所得的结合模式进行了讨论。
